文章基本信息

标题：Implications of Biodiesel-Induced Land-Use Changes for CO₂ Emissions: Case Studies in Tropical America, Africa, and Southeast Asia
本地全文：下载
作者：Wouter M. J. Achten ; Louis V Verchot
期刊名称：Ecology and Society
印刷版ISSN：1708-3087
电子版ISSN：1708-3087
出版年度：2011
卷号：16
期号：4
出版社：The Resilience Alliance
摘要：Biofuels are receiving growing negative attention. Direct and/or indirect land-use changes that result from theircultivation can cause emissions due to carbon losses in soils and biomass and could negate any eventual greenhouse gas (GHG)reduction benefit. This paper evaluates the implications of land-use change emission on the climate-change mitigation potentialof different biofuel production systems in 12 case studies in six countries. We calculated carbon debts created by conversion ofdifferent land-use types, ranging from annual cropland to primary forest. We evaluated case studies using three different biofuelcrops: oil palm, Jatropha, and soybean. The time needed for each biofuel production system to pay back its carbon debt wascalculated based on a life-cycle assessment of the GHG reduction potentials of the system. Carbon debts range from 39 to 1743.7Mg C02ha-1. The oil palm case studies created the largest carbon debts (472.8–1743.7 t C02ha-1) because most of the areaexpansion came at the expense of dense tropical forest. The highest debt was associated with plantation on peatland. For allcases evaluated, only soybean in Guarant. do Norte and Alta Floresta, Brazil needed less than one human generation (30 years)to repay the initial carbon debt. Highest repayment times were found for Jatropha (76–310 years) and oil palm (59–220 years)case studies. Oil palm established in peatlands had the greatest repayment times (206–220 years). High repayment times forJatropha resulted from the combined effects of land-cover change and low CO2emission reduction rate. These outcomes raiseserious questions about the sustainability of biofuel production. The carbon implications of conversion of (semi-)natural systemswith medium to high biomass indicate that, in order to generate climate benefits, cultivation of biofuel feedstocks should berestricted to areas that already have low carbon content
关键词：carbon; carbon debt; greenhouse gas; life-cycle assessment; repayment time